63A main panel fuse blows if power outage occurs

Irish Steve

The plot thickens considerably, we were up with the family yesterday, and the fault is very strange indeed, after the first fuse blew on Friday, before the second fuse was switched in, ALL the MCB's were switched off, so in theory, nothing live or connected, and despite that precaution, the second fuse blew instantly, which is even more confusing, there should have been no load on the fuse when the switch was closed.

Have a local REC coming over next week with the relevant test equipment to see what he can find, but having talked to him, he's also not sure what to make of this scenario, and to confirm a suspicion, this behaviour has only started since the new smart meter was fitted, there were never any issues prior to that happening.

10-10-20

https://www.boards.ie/discussion/comment/121796079#Comment_121796079

How odd. What type of switch is being used? Any chance the switch contacts are damaged?

Shoog

I would be looking to get the ESB to come out and check their wiring. A bad connection can cause voltage spikes which will only manifest at power on.

Irish Steve

https://www.boards.ie/discussion/comment/121796102#Comment_121796102

No way I can check, it's the screw in fuse holder with a close to make after fitting the fuse, we've got several in panels here, and I've never known an issue with them, but at this stage, anything is possible, so all we can do to try and find a solution is literally check everything, and our REC is going to have a quiet chat with a friend in ESB to see if there's any issues they are aware of, there's been nothing in their notes system that normally lets them know about ongoing issues, he's as confused as I am with this one, and I'd trust his awareness of 'issues', so all we can do for now is test and see what shows up.

Irish Steve

https://www.boards.ie/discussion/comment/121796173#Comment_121796173

We're at the point where we may have to get ESB to come and check that there's nothing strange going on with the mini pillar connections, or with the smart meter, it's looking like that may have to be the way to go forward, but they're more likely to respond to a request from a REC after he's tested than they are to me, if I ring, they'll just say to get an REC to test the panel and system, which is our next move.

Shoog

https://www.boards.ie/discussion/comment/121796278#Comment_121796278

Say you are concerned about a potential fire from arcing. I would guess it more likely to be an issue outside the house between you and the step down transformer.

Blowing 63A fuses is a serious health and safety issue since the spike is usually much higher than that.

tomhammer..

First thing is to examine the board and fuse unit before involving ESBN

That doesn't sound like an upstream issue at all

This is the main switchfuse and everything was off ?

No other boards fed directly from the main switch fuse ?

Irish Steve

it is the main switchfuse, and yes, all breakers were off, and there's no other boards fed separately, the one panel controls everything in the house, so in theory, there was no load as such when the fuse was connected, that's what's so confusing, but until we can do some specific testing, we're in the dark on this issue.

tomhammer..

Didn't you have a generator if I recall ?

Is that possibly involved someway?

What's happening when you fit a 2nd main fuse ?

Is everything back operational?

Irish Steve

https://www.boards.ie/discussion/comment/121796363#Comment_121796363

the generator is here, and we're 3 phase, this is happening at the daughter's house in Duleek, only an absolutely bog standard single phase residential system, and the present scenario is that the third fuse on Friday got them back on line, but it's blown one since, on Sunday, nothing since. Our REC is coming out to have a close look next week, that's his first available slot, and we're going to have a much closer look at everything, including rattling the cables to the smart meter, and if it tests good, then we'll have to get ESB involved on the basis of the rest of it tests good, and see what they have to say, and take it from there.

Bruthal.

Ruling out DB flex wiring link problem would be next, after fuse blown with no mcbs on.

Like a Phase-N/E short or something within the DB link wiring. Between a neutral flex and busbar for an example.

tomhammer..

https://www.boards.ie/discussion/comment/121797811#Comment_121797811

Seems a very unusual issue

You'd have to think the answer lies inside the DB

Even if it's that , the fuse is blowing on power restoration so presumably nothing is being disturbed at the board ie: by the operation of the switchfuse

Can't think where else the issue be

Bruthal.

Well the fuse can't blow unless there is some sort of a closed circuit downstream of it you would think.

Irish Steve

Well, interesting is not even close, I've just had a very thought provoking call from the REC, and he's been talking to a friend of his that's working for ESB, and as a result of that conversation, he's telling me that at the moment, there's no point him coming out to have a look at the house, as he won't find a fault, it seems that there is a known issue with Smart meters, and ESB are replacing significant numbers of smart meters because they are causing exactly the sort of problem that is happening at my daughter's, it's some sort of very strange issue internal to the meter and the components inside it, he didn't get the full exact story, but it is a known issue which has resulted in ESB having to change to a new supplier in an attempt to get away from the problem.

Ir will have to be addressed by ESB, so the next move will be to ring ESB networks, and get them out to test the meter, and from the description given, it is faulty and will need to be replaced, and as my daughter is on the vulnerable customer list, it should happen quite quickly, so that's a phone call tomorrow morning for one or other of us, and I will report back when we get a result one way or the other.

Thanks to everyone who contributed, it's certainly going to be an interesting end result if it is indeed the meter that's the issue, the comment made by his contact was 'avoid smart meters for now if at all possible', which is thought provoking, I don't have to worry for a while, we're 3 phase, and apparently there is no such thing as a smart meter for 3 phase at the moment, which suits me quite nicely, we're on nightsaver, which suits our recent upgrade, we've a new (used) EV that gets charged overnight when it needs it, so staying with nightsaver for now is ideal, as it won't charge fully in four hours.

tomhammer..

Makes no sense the upstream meter blowing consumers fuse

Sure it's not ESBN fuse in that scenario

That's up there with smart meters tripping RCDS

meercat

As an interim measure I’d ask your rec to do an insulation resistance test on the entire installation

id also ask him to replace the switch fuse for a 63amp mcb.

esbn will charge for a call-out if it’s not their issue.

tomhammer..

Rec should be out urgently to check main board IR etc and change fuse unit as above

I'd believe that scenario about smart meter causing it if i seen it

Irish Steve

Apparently, it is taking out the CU fuse, and yes, it's caused a lot of confusion, I too would have expected the protect fuse to be the one that goes, apparently not, and it's not a case of the REC not wanting to come out, so I think a call to them, and we'll see what happens.

tomhammer..

https://www.boards.ie/discussion/comment/121799520#Comment_121799520

REC shouldn't have to be asked

He's giving Steve very bad advice saying there's no point coming out nothing to see

That's a big presumption

meercat

https://www.boards.ie/discussion/comment/121799601#Comment_121799601

100% agree

Doolittle51

It must be a combination of things causing the issue. You said the fuse blew when you had all mcbs off? A fuse can't blow if there's no path for the current to flow.

With that in mind, one possible scenario is reverse polarity. But there would also have to be a N-E fault within the property (quite possible) and some weird short happening momentarily in the meter when power is restored.

Some of the cheap plug in socket testers will identify reverse polarity, and can also identify N-E faults on socket circuits. Would be an easy thing to check yourself if you can get your hands on one.

Irish Steve

OK, that's a bit confused, he's not saying to me he won't come out, not at all, but he's saying that with the known issue of meters hopping fuses, there's no advantage him coming out until the meter has been sorted, and with the description of the fault, (we had a LONG chat about it here a couple of days ago, he fitted an EV charger here for me last week), his friend in ESB said that it's a very much known issue, and there won't be a fault on the consumer side of things, so we're better holding fire until ESB have been out, and he will be surprised if there'a an issue after they've been out, given the history.

tomhammer..

So did this problem of fuses blowing after a power cut only start happening after the smart meter was installed ?

tomhammer..

A problem with the smart meter theory is the below

When you changed the second fuse you weren't switching in any load on the smart meter but the fuse blew

There was effectively no change on the load side of meter

"after the first fuse blew on Friday, before the second fuse was switched in, ALL the MCB's were switched off, so in theory, nothing live or connected, and despite that precaution, the second fuse blew instantly"

Irish Steve

https://www.boards.ie/discussion/comment/121799933#Comment_121799933

yes, there was never an issue in the previous 20 years, and it's only become significant after the scheduled outage last friday, there's been 6 fuses blown since, three of them getting the power back on after they restored it, and this morning, it went with one TV and a light on, no other loads active. Another electrician suggested that it was a smart meter related issue when the first fuse blew not long after it was fitted, but it's not been a major issue until the weekend,

meercat

https://www.boards.ie/discussion/comment/121800096#Comment_121800096

I wonder if they upgraded the main neutral/earth link whilst replacing the meter. Did they replace the cutout also. This may mean a better earth in your installation,causing a fuse to blow where beforehand it wouldn’t

a loop impedance test along with an insulation resistance test should be done

tomhammer..

https://www.boards.ie/discussion/comment/121800096#Comment_121800096

6 fuses blown since the outage ?

I believe it's not smart meter related based on the post above this one

I'd get a rec and check installation, voltages etc , and also look at possible esbn issues (?)

Irish Steve

https://www.boards.ie/discussion/comment/121800090#Comment_121800090

the REC contact in ESB did specifically mention that this is one of the symptoms of the meter fault, and yes, I too found it slightly incredible, as you say in theory, nothing is flowing, nothing is connected, but if they are saying that's what's happening, I'm not about to argue with the people who are a lot closer to this than I am.

It's been a while since I was working with stuff like this, it was a very long time ago now, we had a site in the UK that got wired with a non standard socket, to prevent cleaners removing the plug to use it for their vacuum, as it was a small computer that ran 24/5, only off over weekends, and on this particular site, it was wired in MICC, for fire reasons, and it worked with no issues for 3 years, then one weekend, it didn't start up correctly on Monday, so we got called in, and spent several days trying to work out why it wasn't working and back then, if we didn't fix it in a couple of days, the bank would ship in a replacement terminal to get them going again.

We set the new unit up out in the back room, got it all working, and then swapped the machines over, and as part of that, swapped the plug over to allow it to be connected in the right location, pressed the on button, and the replacement machine failed in exactly the same way as the original, at which point, we were in to investigating the socket, and we found that the spark that fitted it hadn't put in one essential short piece of wire, the MICC gland terminated the cable in the metal box, but he hadn't put a wire from the box terminal on to the effectively floating earth pin in the plastic insulated socket, so the earth was floating, and the computer depended on having a viable earth, and without it, the ground voltage floated up to about +2.5v, so the logic systems that depended on zero or plus 5 were all getting horribly confused. The issue was that without changing anything, or moving anything, it had worked for 3 years like that. The fix was easy, the spark came in and fitted the piece of wire that should have been there from day 1, and it all worked perfectly. as did the machine that was out in the back office. The exact reason was never determined, and we'd not been given any reason to suspect the power in that it had been signed off on install, and had worked perfectly for 3 years. Since then, I've been open to listen to all possible theories about reasons for a fault ,because sometimes, even though they come out of left base, they're right.

tomhammer..

https://www.boards.ie/discussion/comment/121800222#Comment_121800222

The most logical explanation is still an issue at the board

Bruthal.

It is like saying a fuse is connected to the incoming phase via the smart meter and the other side of the fuse is connected to nothing, and yet the fuse is blowing due to some strange meter problem. It would be an interesting explanation as to where the current required to blow the fuse, is going.